Electrode for lithium secondary battery, method of manufacturing the electrode, and lithium secondary battery including the electrode

Abstract

An electrode for a lithium secondary battery includes a silicon-based alloy, and has a surface roughness of about 1 to about 10 μm and a surface roughness deviation of 5 μm or less. A method of manufacturing the electrode includes mixing an electrode composition, milling the composition, coating the milled composition on a current collector, and drying the milled composition. A lithium secondary battery includes the electrode.

What is claimed is: 
     
       1. An electrode for a lithium secondary battery, comprising an electrode active material comprising a silicon-based alloy, the electrode having a surface roughness of about 1 to about 10 μm and a surface roughness deviation of about 5 μm or less, the electrode having a mixed density of about 0.80 to about 0.90 g/cc, and the silicon-based alloy comprising an alloy selected from the group consisting of Si 68 Al 8 Ni 24 , Si 62 Ti 20 Ni 20 , Si 65 Ti 17.5 Ni 17.5 , and Si 68 Ti 16 Ni 16 . 
     
     
       2. The electrode of  claim 1 , wherein the surface roughness deviation is about 2 μm or less. 
     
     
       3. The electrode of  claim 1 , wherein the electrode active material is a negative electrode active material, and the electrode is a negative electrode. 
     
     
       4. The electrode of  claim 3 , wherein the electrode active material further comprises a second material selected from the group consisting of carbonaceous materials, lithium metal, lithium alloys, silicon-oxide based materials, and combinations thereof. 
     
     
       5. The electrode of  claim 4 , wherein an amount of the second material is about 1 to about 99 parts by weight based on 100 parts by weight of the silicon-based alloy and the second material. 
     
     
       6. A lithium secondary battery, comprising:
 a first electrode comprising the electrode of  claim 1 ; 
 a second electrode; and 
 an electrolyte.